of chicago



J. G. ALTHER PROCESS FOR CRACKING OILS Sept. 25, 1928.

Original Filed Aug. 20. 1920 Patented Sept. 25, 1928.

UNITD STATES PATENT OFFICE.

AssIGNOR To UNIVERSAL'OIL PRODUCTS CORPORATION 0F SOUTH DAKOTA.

PROCESS FOR CRACXING OES.

Application led August 20, 1920, Serial No. 404,745. Renewed June 9, 1926.

This invention relates to improvements in process for cracking oils and refers moreA particularly to that adapted for the production of gasoline or gasoline like bodies from heavier oils such for example as fuel oil or gas oil cuts from crude petroleum.

Among the objects of the invention are to provide a process in which there is a maximum heating surface relative to the volume of oil under treatment; to provide a process in which the flow of the oil is slowest at the hottestpoint, namely, in the lower part of the combustion chamber and is fastest at the cooler points, namely at the upper part of the combustion chamber;`to provide a. process in which the oil is maintained in a larger stream and kflows slower where the greatest heat transfer takes place so as to get a maximum thermal etliciency; to provide a process in which the volume of oil in the stream decreases and the velocity of the oil in the stream increases as the stream passes towards the coolest part of the combustion chamber; to provide a process in which the oil. may be vaporized under a decreased .pressure relative to the pressure in the heating chamber; to provide a process in which the reflux condensate may be returned to the system for further treatment; to provide a novel form of apparatus for carrying out my process and in general to provide a novel form of process and apparatus of the character referred to.

In the drawings, the single figure shows a view with parts in side elevation and parts in vertical section and parts indotted lines of my improved apparatus.

Referring to the drawings, 1 designates a furnace having burner 2, bridge walls 3, flue 4, stack 5 and combustion chamber 6. In the fire box is mounted heating chamber which takes the form of heating coils 7 `connected in series to form, in effect, one continuous coil. The inlet side of the heating coil is connected to 'feed line 8 having control valve 9 and leading to charging pump 10 connected to any suitable source of raw oil supply. The outlet side of the heating coil is provided with transfer line 11 having control valve 12 and connected to vapor chamber 13. This vapor chamber 13 is provided with residue draw-oft' line 14 having control valve 15 and with vapor outlet 16 leading to goose-neck 17. A valve 18 is interposed in the pipe 16 as shown. The goose-neck 17 leads to the bottom of dephlegmator 19. This dephlegmator is provided with .baffling material 20 and is provided at its lower end with a refiux condensate return line 21 leading to the pump 10. A valve 22 is interposed in line 21. The reflux line .21 is also provided with a second line -23 havlngicontrol valve 24 which line 23 leads to any suitable receptacle. By this arrangement the reflux condensate need not be returned to the heating chamber for further treatment. The upper part of the dephlegmator 1s provided with vapor outlet line 25 leading to water condenser coil 26 which in turn 1s connected by 27 to receiver 28. The receiver 28 is provided with pressure gauge 29 and liquid level gauge 30. This receiver also has liquid draw-off pipe 31 having throttle valve 32 and gas outlet valve 33 having throttle valve 34.

If desired, raw oil may be fed into the upper part of thedephlegmator by'means of the plpe 35 having control valve 36. In this case the pum 10 is not connected to any other source o supply and the preheated raw oil mixed with the reflux through the pipe 21 to the pump 10.

If desired, a differential pressure may be maintained on the systemby suitably controlling valves 12 and 18 and if desired a throttle valve 37 may be interposed in the line 25. Vhere a lower pressure is maintained on the vapor chamber and dephlegmator than the heating coils, either the refiux condensate will have to be diverted elsewhere by closing valve 22 and opening valve 24 or else a pump will have to be interposed in line 21. In such case the raw oil may be fed directly to the pump 10 and the valve 36 closed.`

As a feature of the invention the heating coils are progressively decreasing in size; for example, if there are 10 tubes to the coil, the first `tube may be 61/2 inches and the succeeding tubes decrease as vfollows as to their internal diameter: 5% inches, 5% inches, 4% inches, 41A inches, 3% inches, 3% inches, 2% inches, 2% inches and 1% inches. By means of this arrangement it will be seen that the velocity of the oil through the heating coil gradually increases. It is particularly desirable that the oil be maintained in a liquid phase during its passage through the heating coil so as to prevent precipitation of carbon in the coil and consequent clogging up or burning out of the coil.

condensate passesdovvn Je run may be i? say 33o Baume ure of T63" in ined under foresvalve l2 the pressure in the vapor chamber,`

deplilegmator and, water condenser may be reduced to 5() lbs., or ii' desired a pressure of 150 lbs. may be maintained on the heating coii, 100 lbs. on the vapor chamber and 'i5 lbs. in the dephlegmator.

claim as my invention:

i. The process of crackingr petroleum oil, which consists in passing oilin a stream of progressively decreasing size, through a heating zone of progressively7 decreasing temperature, in transferring the oil while in the smallest stream to a vapor chamber, and inremoving vapors from said chamber.

2. The process of cracking petroleum oil, comprising passing the oii through a coil of progressively decreasing size disposed within a heating zone wherein the diameter of the coil decreases in accordance with a lowering temperature in the heating zone, in dischargessere ing the oil from 'die snif coil into a vapor Y from said vapors to a condensing The proce: i

of progressive heating stage ture is applied o the velocity of the oii infrl decreases, in discharging c. t. chamber, and i .Ynoving vapors from said chamber:

4. The process crac which consists passing e in a email stream of progressifv'eiJ4 e reasins size throughnhting stage wherein the condensing r oetroleuni oil,

decreases in diameter and ity as the temperature wi chamber flowers. in disciiai vapor chamber? and in ecting and condensing vapors from said chamber.

o. The process ci? treating petroleum oils, which consists siowiy passing ci). in scream through the hottest portion., of a eating chamber, and in gradualiy decreasing she size of the stream as the temperature the chainber lowers to cause an increase in the velocity of the oil, in collecting the oil in the vapor chamber, and in discharging the vapors from said chamber for condensation and collection.

JOSEPH G. ALTHER. 

